The Claim
In resistance-trained males performing free-weight back squats with maximal intended velocity, gluteus maximus and semitendinosus muscle activation increases with increasing load, with gluteus maximus exhibiting greater activation at 80%–100% of one-repetition maximum (1-RM) compared to 30%–60% 1-RM, and semitendinosus showing progressively increased activation from 30% to 100% 1-RM.
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
When strong guys do fast back squats with heavy weights, their butt and hamstring muscles work harder the heavier the weight gets — especially the butt muscle, which really kicks in when the weight is 80% or more of their max lift.
See the scientific wording
In resistance-trained males performing free-weight back squats with maximal intended velocity, gluteus maximus and semitendinosus muscle activation increases with load, with gluteus maximus showing higher activation at 80%–100% 1-RM compared to 30%–60% 1-RM, and semitendinosus increasing activation from 30% to 100% 1-RM.
What the research says
1 studyStudy: Comparison of muscle activation and kinematics during free-weight back squats with different loads
The study found that when people squat with heavier weights as fast as possible, their glutes and hamstrings work harder, especially at the heaviest weights — which matches what the claim says.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.